Position sensors are used as input devices for computers, personal digital assistants (PDAs), media players, video game players, consumer electronics, cellular phones, payphones, point-of-sale terminals and the like. One common type of position sensor is the touchpad-type sensor, which can be readily found, for example, as an input device on many notebook-type computers. A user generally operates the touchpad by moving a finger, stylus or other pointer near a sensing surface to move a cursor or other indicator on a display screen. A capacitive or inductive proximity sensor and/or a resistive touch sensor within the device senses the position of the finger or pointer, and suitably relays an electrical and/or electronic indication of the position to the computer or other host. One example of a touchpad that is based on capacitive sensing technologies is described in U.S. Pat. No. 5,880,411, which issued to Gillespie et al. on Mar. 9, 1999. Position sensors have also been combined with liquid crystal display technologies to create touch sensitive displays for notebook-type computers, PDAs, point of sale terminals, automatic teller machines, kiosks and the like.
Although position sensors have been widely adopted, designers continue to look for ways to improve the sensors' appearance and functionality. In particular, difficulties have long been realized in illuminating or otherwise producing light effects on the sensor. Some touch-sensitive displays have been illuminated with backlighting from a fluorescent lamp or other source. This technique has several inherent disadvantages, however, most notably that the sensors used in such devices must typically be made transparent or translucent so that light is able to pass through the sensor to the observer's eye. Although such sensors may be fabricated from materials such as Indium Tin Oxide (ITO), these materials have generally been found to be disadvantageous in terms of cost, manufacturability, design flexibility, performance and the like. Moreover, ITO can be somewhat absorptive, thereby partially obscuring the display. Even further, ITO is frequently subject to wear and cracking in use, thereby limiting the lifetime of the sensor.
Accordingly, it is desirable to provide a position sensor that is capable of producing a light effect that modifies the appearance of the position sensor. In addition, it is desirable to produce the light effect without requiring a transparent or translucent touch sensor. Moreover, it is desirable to create a position sensor that provides position-sensitive soft control and/or status indicator regions without requiring a liquid crystal or other display. Other desirable features and characteristics of the present invention will become apparent from the subsequent detailed description and the appended claims, taken in conjunction with the accompanying drawings and the foregoing technical field and background.